WB does actually own the Ruby-Spears library of cartoons. While R-S initially left Hanna-Barbera to start their own animation house with Filmways as their backer, Filmways faced financial trouble a couple years later and was acquired by Orion Pictures, and they in turn sold the studio back to Taft Broadcasting, which owned H-B. (I've always felt bad for them over this - here they are trying to go on their own, and they end up right back where they were trying to escape!) While the two studios ran concurrent for a while, R-S was basically folded and absorbed into the H-B library, and when Taft sold H-B to Turner Broadcasting, all the R-S toons came in the deal. Therefore, it is possible that "GOLDIE GOLD" could pop up.
However, it is not likely that any of the H-B sitcom spinoff cartoons will surface, as the intellectual property rights belong to the studios of origin; "JEANNIE" and "PARTRIDGE FAMILY 2200" are owned by Sony Television, the Fonzie, Laverne & Shirley, and Mork & Mindy cartoons are owned by CBS. "THE DUKES" could show up since that was a WB property anyway.
Remind me, were there any musical numbers in "JOSIE AND THE PUSSYCATS IN OUTER SPACE"? I recall that there was a lot of expense involved to clear the songs for the original series release on DVD (ditto for the Rhino Handmade "greatest hits" CD), and if there are more songs in this series, WB may have decided it's not worth spending the money to clear them.